Route Parameters
Capture dynamic segments of the URL with @Param and query values with @Query.
Syntax
@Get(':id') findOne(@Param('id') id: string)Routes often contain dynamic parts, like an id. Declare them in the path with a colon and read them with the @Param() decorator.
Params vs query
- Route params - part of the path, e.g.
/users/42. Read with@Param('id'). - Query params - after the
?, e.g./users?role=admin. Read with@Query('role').
Values arrive as strings; convert or validate them with pipes when you need numbers.
Example
import { Controller, Get, Param, Query } from '@nestjs/common';
@Controller('users')
export class UsersController {
@Get(':id') // GET /users/42
findOne(@Param('id') id: string) {
return `user ${id}`;
}
@Get() // GET /users?role=admin
findByRole(@Query('role') role: string) {
return `role ${role}`;
}
}When to use it
- A developer uses @Param("id") to extract the product ID from GET /products/42 and fetch the matching record from the database.
- An API uses @Query("page") and @Query("limit") to implement paginated list endpoints without putting pagination data in the URL path.
- A developer uses @Param() (no argument) to receive the full params object when a route has multiple dynamic segments like /orgs/:orgId/repos/:repoId.
More examples
Single route parameter
Shows how @Param("id") extracts the dynamic :id segment from the URL path.
import { Controller, Get, Param } from '@nestjs/common';
@Controller('products')
export class ProductsController {
@Get(':id')
findOne(@Param('id') id: string) {
return { id }; // e.g. GET /products/42 → { id: '42' }
}
}Query parameters for pagination
Demonstrates reading optional query parameters with defaults for a paginated list endpoint.
import { Controller, Get, Query } from '@nestjs/common';
@Controller('posts')
export class PostsController {
@Get()
findAll(
@Query('page') page = '1',
@Query('limit') limit = '10',
) {
return { page: +page, limit: +limit };
}
}Multiple path params object
Uses @Param() without a key to receive the full params object when there are multiple dynamic segments.
import { Controller, Get, Param } from '@nestjs/common';
@Controller('orgs/:orgId/repos')
export class ReposController {
@Get(':repoId')
findOne(@Param() params: Record<string, string>) {
const { orgId, repoId } = params;
return { orgId, repoId };
}
}
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